Materials for electronic devices

ABSTRACT

The invention relates to compounds comprising functional substituents in a specific spatial arrangement, devices containing same, and the preparation and use thereof.

The present invention relates to cyclic compounds having a specificarrangement of electron-conducting and hole-conducting groups, to theuse thereof in electronic devices, to the production thereof and toelectronic devices.

The structure of organic electroluminescent devices (e.g. OLEDs—organiclight-emitting diodes or OLECs—organic light-emitting electrochemicalcells) in which organic semiconductors are used as functional materialsis described, for example, in U.S. Pat. Nos. 4,539,507, 5,151,629, EP0676461 and WO 98/27136. Emitting materials used here, as well asfluorescent emitters, are increasingly organometallic complexes whichexhibit phosphorescence (M. A. Baldo et al., Appl. Phys. Lett. 1999, 75,4-6). For quantum-mechanical reasons, up to four times the energyefficiency and power efficiency is possible using organometalliccompounds as phosphorescent emitters. In general terms, both in the caseof OLEDs which exhibit singlet emission and in the case of OLEDs whichexhibit triplet emission, there is still a need for improvement,especially with regard to efficiency, operating voltage and lifetime.This is especially true of OLEDs which emit in the shorter-wave range,i.e. green and especially blue.

The properties of organic electroluminescent devices are not onlydetermined by the emitters used. Also of particular significance hereare especially the other materials used, such as host and matrixmaterials, hole blocker materials, electron transport materials, holetransport materials and electron or exciton blocker materials.Improvements to these materials can lead to distinct improvements toelectroluminescent devices.

According to the prior art, ketones (for example according to WO2004/093207 or WO 2010/006680) or phosphine oxides (for exampleaccording to WO 2005/003253) are among the matrix materials used forphosphorescent emitters. Further matrix materials according to the priorart are represented by triazines (for example WO 2008/056746, EP0906947, EP 0908787, EP 0906948).

For fluorescent OLEDs, according to the prior art, fused aromatics inparticular, especially anthracene derivatives, are used as hostmaterials for blue-emitting electroluminescent devices in particular,for example 9,10-bis(2-naphthyl)anthracene (U.S. Pat. No. 5,935,721). WO03/095445 and CN 1362464 disclose 9,10-bis(1-naphthyl)anthracenederivatives for use in OLEDs. Further anthracene derivatives aredisclosed in WO 01/076323, in WO 01/021729, in WO 2004/013073, in WO2004/018588, in WO 2003/087023 or in WO 2004/018587. Host materialsbased on aryl-substituted pyrenes and chrysenes are disclosed in WO2004/016575. Host materials based on benzanthracene derivatives aredisclosed in WO 2008/145239. It is desirable for high-value applicationsto have improved host materials available.

The prior art discloses the use of compounds containing one or morecarbazole groups in electronic devices, known, for example, in WO2005/039246, US 2005/0069729, JP 2004/288381, EP 1205527 or WO2008/086851.

The prior art further discloses the use of compounds containing one ormore indenocarbazole groups in electronic devices, known, for example,in WO 2010/136109 and WO 2011/000455.

The prior art further discloses the use of compounds containing one ormore electron-deficient heteroaromatic six-membered rings in electronicdevices, known, for example, in WO 2010/015306, WO 2007/063754 and WO2008/056746.

WO 2009/069442 discloses tricyclic systems such as carbazole,dibenzofuran or dibenzothiophene having a high level of substitution byelectron-deficient heteroaromatics (e.g. pyridine, pyrimidine ortriazine). The tricyclic systems are not substituted by hole-conductinggroups, i.e. electron-rich groups.

JP 2009-21336 discloses substituted carbazoles as matrix materials,where the carbazoles are substituted by an electron-conducting group andby a hole-conducting group. However, the compounds do not have anyface-to-face substitution.

WO 2011/057706 discloses substituted carbazoles as matrix materials,where the carbazoles are substituted by an electron-conducting group andby a hole-conducting group. However, most of the carbazoles disclosed donot have any face-to-face substitution. In the individual face-to-facearrangements disclosed, however, the hole- or electron-conducting groupis bonded directly to the tricyclic system.

However, there is still a need for improvement in the case of use ofthese materials, and likewise of other materials, especially in relationto the efficiency and lifetime of the device.

It is therefore an object of the present invention to provide compoundssuitable for use in a fluorescent or phosphorescent OLED, for example ashost and/or matrix material or as hole transport/electron blockermaterial or exciton blocker material, or as electron transport or holeblocker material, and which lead to good device properties when used inan OLED, and to provide the corresponding electronic device.

It has been found that, surprisingly, particular compounds described indetail below achieve these objects and lead to good properties of theorganic electroluminescent device, especially with regard to lifetime,efficiency and operating voltage. Electronic devices, especially organicelectroluminescent devices, containing such compounds, and thecorresponding preferred compounds, are therefore provided by the presentinvention. The surprising effects are achieved through a specificarrangement (“face-to-face”, i.e. mutually opposite arrangement ofgroups) of electron-conducting and hole-conducting groups in compoundsof the formulae adduced below. Without being bound to a theory, therapid charge transport could be because of the relatively well-defined(highly ordered) parallel alignment of the molecules (face-to-facearrangement), in which there is a certain short-range order of themolecules. Because of the short distances between the groups,intermolecular interactions, for example direct π-π interaction, couldbe one of the causes of the rapid charge transfer.

The compounds of the invention also have a high glass transitiontemperature (T_(g)), which is advantageous in terms of the processing ofthe compounds in the production of electronic devices. The high glasstransition temperature of the compounds also permits the use of thecompounds in thin amorphous organic layers.

Moreover, the compounds of the invention allow stabilization of thecharge carriers in the excited state and have sufficiently high tripletenergy, which is an important prerequisite for phosphorescent devices.Furthermore, the compounds of the invention have improved performancedata in OLEDs compared to the compounds from the prior art.

The present invention therefore provides compounds of the general

where the symbols and indices used are as follows:

-   A and A′ are the same or different and are an aromatic or    heteroaromatic ring which has 5 or 6 ring atoms and may be    substituted by one or more R¹ radicals which may be independent of    one another;    -   G¹, G² are the same or different at each instance and are an        organic electron-transporting group (ETG) from the group of the        electron-deficient heteroaromatic groups, the ETGs preferably        being a heteroaryl group having 5 to 60 aromatic ring atoms,        N-containing heteroaryl groups being very preferred heteroaryl        groups, and most preferred ETGs being selected from the group of        the triazines, pyrimidines, pyrazines and pyridines;    -   or an electron-rich organic group which conducts holes (LTG),        the LTGs preferably being selected from the group of the        arylamines, triarylamines, bridged amines, preferred bridged        amines being dihydroacridines, dihydrophenazines, phenoxazines        and phenothiazines, carbazoles, bridged carbazoles,        biscarbazoles, indenocarbazoles and indolocarbazoles,    -   where at least one of the two G¹ and G² groups must be an        electron-transporting group (ETG) and where the G¹ and G² groups        may be substituted by one or more independent R¹ radicals;-   Ar¹ is, when G¹ is an electron-transporting group, a bivalent    aromatic or heteroaromatic, preferably aromatic, ring or ring system    having 5 to 60 ring atoms, where the ring or ring system is bridged    neither with the ring system comprising the A and A′ rings nor with    the ETG, it being preferable when Ar¹ is a pyridylene, pyrimidylene,    phenylene, biphenylene or fluorene, spiro, terphenylene, thiophene    or furan group, preference being given particularly to a phenylene,    biphenylene or terphenylene group and very particularly to a    phenylene group,    -   or, when G¹ is a hole-transporting group, an aromatic ring or        ring system having 5 to 60 ring atoms, where the ring or ring        system is bridged neither with the ring system comprising the A        and A′ rings nor with the LTG, it being preferable when Ar¹ is a        phenylene, biphenylene or terphenylene group and particular        preference being given to a phenylene group;-   Ar² is, when G² is an electron-transporting group, a bivalent    aromatic or heteroaromatic ring or ring system having 5 to 60 ring    atoms, where the ring or ring system is bridged neither with the    ring system comprising the A and A′ rings nor with the ETG, it being    preferable when Ar² is a pyridylene, pyrimidylene, phenylene,    biphenylene or fluorene, spiro, terphenylene, thiophene or furan    group, preference being given particularly to a phenylene,    biphenylene or terphenylene group and very particularly to a    phenylene group,    -   or, when G² is a hole-transporting group, an aromatic ring or        ring system having 5 to 60 ring atoms, where the ring or ring        system is bridged neither with the ring system comprising the A        and A′ rings nor with the LTG, it being preferable when Ar² is a        phenylene, biphenylene or terphenylene group and particular        preference being given to a phenylene group;-   V is a single bond, C═O, C(R¹)₂, NAr³, O, S, Si(R¹)₂, BR¹, PR¹,    P(═O)R¹, SO or SO₂, where, in the case of a single bond, the carbon    atoms of the A and A′ rings are joined directly to one another by a    single bond, preference being given to a single bond, C(R¹)₂, NAr³,    O and S, particular preference being given to a single bond, C(R¹)₂,    O and S, very particular preference to O and S and especial    preference to O;-   W is a single bond, C═O, C(R¹)₂, NR¹, O, S, Si(R¹)₂, BR¹, PR¹,    P(═O)R¹, SO or SO₂, where, in the case of a single bond, the carbon    atoms of the A and A′ rings are joined directly to one another by a    single bond, preference being given to a single bond, C(R′)₂, NR¹, O    and S, particular preference being given to a single bond, C(R¹)₂, O    and S, very particular preference to O and S and especial preference    to O;    -   where it is further preferable that V is a single bond if W is        not a single bond or that W is a single bond if V is not a        single bond;    -   where it is further very preferable that V is a single bond if W        is O or S or that W is a single bond if V is O or S;    -   where it is further very particularly preferable that V is a        single bond if W is O or that W is a single bond if V is O;-   m is either 0 or 1;-   n is either 0 or 1,    -   where m=n;-   p is either 0 or 1;-   q is either 0 or 1, where p+q is either 1 or 2, it being preferable    when p+q=1;-   Ar³ is an aromatic or heteroaromatic ring or ring system having 5 to    30 ring atoms, where the ring or the may each be substituted by one    or more R² radicals which may be substituted by one or more R³    radicals, where two or more R² radicals together may form a ring;-   R¹ is the same or different at each instance and is H, D, F, Cl, Br,    I, N(R²)₂, CN, NO₂, Si(R²)₃, B(OR²)₂, C(═O)R², P(═O)(R²)₂, S(═O)R²,    S(═O)₂R², OSO₂R², a straight-chain alkyl, alkoxy or thioalkoxy group    having 1 to 40 carbon atoms or a straight-chain alkenyl or alkynyl    group having 2 to 40 carbon atoms or a branched or cyclic alkyl,    alkenyl, alkynyl, alkoxy, alkylalkoxy or thioalkoxy group having 3    to 40 carbon atoms, each of which may be substituted by one or more    R² radicals, where one or more nonadjacent CH₂ groups may be    replaced by R²C═CR², C≡C, Si(R²)₂, Ge(R²)₂, Sn(R²)₂, C═O, C═S, C═Se,    C═NR², P(═O)(R²), SO, SO₂, NR², O, S or CONR² and where one or more    hydrogen atoms may be replaced by D, F, Cl, Br, I, CN or NO₂, or an    aromatic or heteroaromatic ring system which has 5 to 60 aromatic    ring atoms and may be substituted in each case by one or more R²    radicals, or an aryloxy, arylalkoxy or heteroaryloxy group which has    5 to 60 aromatic ring atoms and may be substituted by one or more R²    radicals, or a diarylamino group, diheteroarylamino group or    arylheteroarylamino group which has 10 to 40 aromatic ring atoms and    may be substituted by one or more R² radicals, or a combination of    two or more of these groups or a crosslinkable Q group;-   R² is the same or different at each instance and is H, D, F, Cl, Br,    I, N(R³)₂, CN, NO₂, Si(R³)₃, B(OR³)₂, C(═O)R³, P(═O)(R³)₂, S(═O)R³,    S(═O)₂R³, OSO₂R³, a straight-chain alkyl, alkoxy or thioalkoxy group    having 1 to 40 carbon atoms or a straight-chain alkenyl or alkynyl    group having 2 to 40 carbon atoms or a branched or cyclic alkyl,    alkenyl, alkynyl, alkoxy, alkylalkoxy or thioalkoxy group having 3    to 40 carbon atoms, each of which may be substituted by one or more    R³ radicals, where one or more nonadjacent CH₂ groups may be    replaced by R³C═CR³, C≡C, Si(R³)₂, Ge(R³)₂, Sn(R³)₂, C═O, C═S, C═Se,    C═NR³, P(═O)(R³), SO, SO₂, NR³, O, S or CONR³ and where one or more    hydrogen atoms may be replaced by D, F, Cl, Br, I, CN or NO₂, or an    aromatic or heteroaromatic ring system which has 5 to 60 aromatic    ring atoms and may be substituted in each case by one or more R³    radicals, or an aryloxy, arylalkoxy or heteroaryloxy group which has    5 to 60 aromatic ring atoms and may be substituted by one or more R³    radicals, or a diarylamino group, diheteroarylamino group or    arylheteroarylamino group which has 10 to 40 aromatic ring atoms and    may be substituted by one or more R³ radicals, or a combination of    two or more of these groups; at the same time, two or more adjacent    R² radicals together may form a mono- or polycyclic, aliphatic or    aromatic ring system;-   R³ is the same or different at each instance and is H, D, F or an    aliphatic, aromatic and/or heteroaromatic hydrocarbyl radical having    1 to 20 carbon atoms, in which one or more hydrogen atoms may also    be replaced by F; at the same time, two or more R³ substituents    together may also form a mono- or polycyclic aliphatic or aromatic    ring system;

with the proviso that not more than one R¹ substituent in the A ring andnot more than one R¹ substituent in the A′ ring contains an aromatic orheteroaromatic group having 5 to 30 ring atoms.

Accordingly, for example, for the compounds of the general formula (1),in the case that m=n=1 and V═W=single bond, the general formula is asfollows:

In addition, for example, for the compounds of the general formula (1),in the case that m=n=1 and V═N—Ar³ and W=single bond, the generalformula is as follows:

In addition, for example, for the compounds of the general formula (1),in the case that m=n=0, the general formula is as follows:

In a preferred embodiment of the present invention, the G¹ and G² groupscontain exclusively one kind of charge-transporting units. This meansthat, for example, if G¹ is an ETG, G¹ cannot contain any groups thatare hole-conducting.

If triazines are used as ETGs, in a further preferred embodiment, thetriazines are in substituted form, meaning that none of the triazines inan ETG may have hydrogen atoms bonded directly to the triazine. If thetriazines still have hydrogen atoms bonded directly to the triazine,this leads to worse performance data of electronic, especiallyelectroluminescent, devices compared to triazines that do not have anyhydrogen atoms bonded directly to the triazine.

In a preferred embodiment, the compound is selected from the generalformula (2)

where the symbols additionally used are as follows:

-   X is the same or different at each instance and is N or CR¹;-   Q is the same or different at each instance and is X═X, S, O or NR¹,    preferably X═X, S and O, very preferably X═X and S and most    preferably X═X.

A very preferred compound is accordingly of the general formulae (3) to(11)

with very particular preference for a compound of the general formulae(3) to (8) and especial preference for a compound of the general formula(4).

It is further very particularly preferable when X in the formulae (1) to(11) is CR¹.

In a preferred embodiment, the present invention relates to a compoundof the formula (4), preferably a compound of the formula (4) where X isCR¹ and m=1, very preferably a compound of the formula (4) where X isCR¹, n=1 and V is O, where the above definitions and preferredembodiments apply to the other symbols and indices.

In a further preferred embodiment, the present invention relates to acompound of the formula (4) where X is CR⁴, m=1 and V is N—Ar³, wherethe above definitions and preferred embodiments apply to the othersymbols and indices.

In a further preferred embodiment, the present invention relates to acompound of the general formula (12)

where V is O or S and where the definitions and preferred embodimentsadduced herein apply to the indices and symbols used. It is verypreferable when V in the compound of the formula (12) is O.

In a further preferred embodiment, the present invention relates to acompound of the general formula (13)

where V is O or S and where the definitions and preferred embodimentsadduced herein apply to the indices and symbols used and where thearomatic rings A and A′ each have not more than one R¹ substituent, i.e.s is 0 or 1 and t is 0 or 1, where s+t may be 0, 1 or 2. It is verypreferable when V in the compound of the formula (13) is O.

In a very preferred embodiment, the present invention relates to acompound of the general formula (14)

where the definitions and preferred embodiments adduced herein apply tothe indices and symbols used and where the aromatic rings A and A′ eachhave not more than one R¹ substituent.

In a very particularly preferred embodiment, the present inventionrelates to a compound of the general formula (15)

where the definitions and preferred embodiments adduced herein apply tothe symbols used and where the aromatic rings each have not more thanone R¹ substituent.

In a further very particularly preferred embodiment, the presentinvention relates to a compound of the general formula (16)

where the definitions and preferred embodiments adduced herein apply tothe symbols used and where the aromatic rings each have not more thanone R¹ substituent.

It is further especially preferable when R¹ in the rings A and A′ in thecompounds of the formulae (12) to (16) is H.

In a preferred embodiment, the sum total of the two indices p and q inthe formulae (12) to (16) is 1.

In another preferred embodiment, the sum total of the two indices p andq in the formulae (12) to (16) is 2.

The wording that two or more radicals together may form a ring, in thecontext of the present application, shall be understood to mean, interalia, that the two radicals are joined to one another by a chemicalbond. This is illustrated by the following scheme:

In addition, however, the abovementioned wording shall also beunderstood to mean that, if one of the two radicals is hydrogen, thesecond radical binds to the position to which the hydrogen atom wasbonded, forming a ring. This shall be illustrated by the followingscheme:

A fused aryl group is understood to mean an aryl group containing two ormore aromatic rings fused to one another, meaning that they share one ormore aromatic bonds. A corresponding definition applies to heteroarylgroups. Examples of fused aryl groups, regardless of the number of ringatoms therein, are naphthyl, anthracenyl, pyrenyl, phenanthrenyl andperylenyl. Examples of fused heteroaryl groups are quinolinyl, indolyl,carbazolyl and acridinyl.

There follow general definitions of chemical groups in the context ofthe present application:

An aryl group in the context of this invention contains 6 to 60 aromaticring atoms, a heteroaryl group in the context of this invention contains5 to 60 aromatic ring atoms, at least one of which is a heteroatom. Theheteroatoms are preferably selected from N, O and S. This is thefundamental definition. If other preferences are stated in thedescription of the present invention, for example with regard to thenumber of aromatic ring atoms or of heteroatoms present, these areapplicable.

An aryl group or heteroaryl group is understood here to mean either asimple aromatic cycle, i.e. benzene, or a simple heteroaromatic cycle,for example pyridine, pyrimidine or thiophene, or a fused (annelated)aromatic or heteroaromatic polycycle, for example naphthalene,phenanthrene, quinoline or carbazole. A fused (annelated) aromatic orheteroaromatic polycycle, in the context of the present application,consists of two or more simple aromatic or heteroaromatic cycles fusedto one another.

An electron-deficient heteroaryl group in the context of the presentinvention is defined as a 5-membered heteroaryl group having at leasttwo heteroatoms, for example imidazole, oxazole, oxadiazole, etc., or asa 6-membered heteroaryl group having at least one heteroatom, forexample pyridine, pyrimidine, pyrazine, triazine, etc. It is alsopossible for further 6-membered aryl or 6-membered heteroaryl groups tobe fused onto these groups, as is the case, for example, inbenzimidazole, quinoline or phenanthroline.

An aryl or heteroaryl group, each of which may be substituted by theabovementioned radicals and which may be joined to the aromatic orheteroaromatic system via any desired positions, is especiallyunderstood to mean groups derived from benzene, naphthalene, anthracene,phenanthrene, pyrene, dihydropyrene, chrysene, perylene, fluoranthene,benzanthracene, benzophenanthrene, tetracene, pentacene, benzopyrene,furan, benzofuran, isobenzofuran, dibenzofuran, thiophene,benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole,isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine,phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline,benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, indazole,imidazole, benzimidazole, naphthimidazole, phenanthrimidazole,pyridimidazole, pyrazinimidazole, quinoxalinimidazole, oxazole,benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole,1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine,pyrimidine, benzopyrimidine, quinoxaline, pyrazine, phenazine,naphthyridine, azacarbazole, benzocarboline, phenanthroline,1,2,3-triazole, 1,2,4-triazole, benzotriazole, 1,2,3-oxadiazole,1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole,1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, 1,3,5-triazine,1,2,4-triazine, 1,2,3-triazine, tetrazole, 1,2,4,5-tetrazine,1,2,3,4-tetrazine, 1,2,3,5-tetrazine, purine, pteridine, indolizine andbenzothiadiazole.

An aryloxy group as defined in the present invention is understood tomean an aryl group as defined above bonded via an oxygen atom. Ananalogous definition applies to heteroaryloxy groups.

An aromatic ring system in the context of this invention contains 6 to60 carbon atoms in the ring system. A heteroaromatic ring system in thecontext of this invention contains 5 to 60 aromatic ring atoms, at leastone of which is a heteroatom. The heteroatoms are preferably selectedfrom N, O and/or S. An aromatic or heteroaromatic ring system in thecontext of this invention is understood to mean a system which does notnecessarily contain only aryl or heteroaryl groups, but in which it isalso possible for two or more aryl or heteroaryl groups to be bonded bya nonaromatic unit (preferably less than 10% of the atoms other than H),for example an sp³-hybridized carbon, silicon, nitrogen or oxygen atom,an sp²-hybridized carbon or nitrogen atom or an sp-hybridized carbonatom. For example, systems such as 9,9′-spirobifluorene,9,9′-diarylfluorene, triarylamine, diaryl ethers, stilbene, etc. arealso to be regarded as aromatic ring systems in the context of thisinvention, and likewise systems in which two or more aryl groups arejoined, for example, by a linear or cyclic alkyl, alkenyl or alkynylgroup or by a silyl group. In addition, systems in which two or morearyl or heteroaryl groups are joined to one another via single bonds arealso to be regarded as aromatic or heteroaromatic ring systems in thecontext of this invention, for example systems such as biphenyl,terphenyl or diphenyltriazine.

An aromatic or heteroaromatic ring system which has 5-60 aromatic ringatoms and may also be substituted in each case by radicals as definedabove and which may be joined to the aromatic or heteroaromatic systemvia any desired positions is especially understood to mean groupsderived from benzene, naphthalene, anthracene, benzanthracene,phenanthrene, benzophenanthrene, pyrene, chrysene, perylene,fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl,biphenylene, terphenyl, terphenylene, quaterphenyl, fluorene,spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene,cis- or trans-indenofluorene, truxene, isotruxene, spirotruxene,spiroisotruxene, furan, benzofuran, isobenzofuran, dibenzofuran,thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole,indole, isoindole, carbazole, indolocarbazole, indenocarbazole,pyridine, quinoline, isoquinoline, acridine, phenanthridine,benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline,phenothiazine, phenoxazine, pyrazole, indazole, imidazole,benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole,pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole,naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1,2-thiazole,1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine,benzopyrimidine, quinoxaline, 1,5-diazaanthracene, 2,7-diazapyrene,2,3-diazapyrene, 1,6-diazapyrene, 1,8-diazapyrene, 4,5-diazapyrene,4,5,9,10-tetraazaperylene, pyrazine, phenazine, phenoxazine,phenothiazine, fluorubine, naphthyridine, azacarbazole, benzocarboline,phenanthroline, 1,2,3-triazole, 1,2,4-triazole, benzotriazole,1,2,3-oxadiazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole,1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole,1,3,4-thiadiazole, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine,tetrazole, 1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine,purine, pteridine, indolizine and benzothiadiazole or combinations ofthese groups.

In the context of the present invention, a straight-chain alkyl grouphaving 1 to 40 carbon atoms and a branched or cyclic alkyl group having3 to 40 carbon atoms and an alkenyl or alkynyl group having 2 to 40carbon atoms in which individual hydrogen atoms or CH₂ groups may alsobe replaced by the groups mentioned above in the definition of theradicals are preferably understood to mean the methyl, ethyl, n-propyl,i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl,s-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexyl,n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl,trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, ethenyl,propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl,heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl,butynyl, pentynyl, hexynyl or octynyl radicals. An alkoxy or thioalkylgroup having 1 to 40 carbon atoms is preferably understood to meanmethoxy, trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy,i-butoxy, s-butoxy, t-butoxy, n-pentoxy, s-pentoxy, 2-methylbutoxy,n-hexoxy, cyclohexyloxy, n-heptoxy, cycloheptyloxy, n-octyloxy,cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy,2,2,2-trifluoroethoxy, methylthio, ethylthio, n-propylthio,i-propylthio, n-butylthio, i-butylthio, s-butylthio, t-butylthio,n-pentylthio, s-pentylthio, n-hexylthio, cyclohexylthio, n-heptylthio,cycloheptylthio, n-octylthio, cyclooctylthio, 2-ethylhexylthio,trifluoromethylthio, pentafluoroethylthio, 2,2,2-trifluoroethylthio,ethenylthio, propenylthio, butenylthio, pentenylthio, cyclopentenylthio,hexenylthio, cyclohexenylthio, heptenylthio, cycloheptenylthio,octenylthio, cyclooctenylthio, ethynylthio, propynylthio, butynylthio,pentynylthio, hexynylthio, heptynylthio or octynylthio.

When G¹ or G² is an electron-transporting group (ETG), the group ispreferably an electron-deficient heteroaromatic group which may besubstituted by one or more R¹ radicals. Even more preferred areaccordingly heteroaromatic groups having 6 aromatic ring atoms of whichat least one is a nitrogen atom, or heteroaromatic groups having 5aromatic ring atoms of which at least 2 are heteroatoms, and preferablyat least one of them a nitrogen atom which may be substituted by R¹,where further aryl or heteroaryl groups may also be fused onto each ofthese groups.

Preferred electron-deficient heteroaromatic groups are selected from thefollowing groups:

where the dotted bond marks the attachment position, R¹ is as definedabove and

-   Q′ is the same or different at each instance and is CR¹ or N, and-   Q″ is NR¹, O or S;

where at least one Q′ is N and/or at least one Q″ is NR¹.

Preferred examples of electron-deficient heteroaromatic groups are:pyridines, pyrazines, pyrimidines, pyridazines, 1,2,4-triazines,1,3,5-triazines, quinolines, isoquinolines, quinoxalines, pyrazoles,imidazoles, benzimidazoles, thiazoles, benzothiazoles, oxazoles orbenzoxazoles, each of which may be substituted by R¹. Even morepreferably, the electron-transporting group is a pyridine, pyrazine,pyrimidine, pyridazine and 1,3,5-triazine substituted by one or more R¹radicals.

Very preferred electron-deficient heteroaromatic groups are selectedfrom the following groups:

The R¹ substituents in the ETG are preferably selected from the groupconsisting of H and an aromatic or heteroaromatic ring system having 5to 60 aromatic ring atoms, each of which may be substituted by one ormore R² radicals.

Examples of very particularly preferred ETGs having R¹ radicals are thefollowing groups which may be substituted by one or more independent R²radicals, where the dotted bonds indicate the binding positions to theAr¹ and Ar² groups.

The electron transport group preferably has a LUMO (lowest unoccupiedmolecular orbital) energy of less than −1.3 eV, very preferably lessthan −2.5 eV and most preferably less than −2.7 eV.

HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupiedmolecular orbital) energy levels and the energy of the lowest tripletstate Ti and that of the lowest excited singlet state Si of thematerials are determined via quantum-chemical calculations. For thispurpose, the “Gaussian09 W” (Gaussian Inc.) software package is used.For calculation of organic substances, an optimization of geometry isfirst conducted by the “Ground State/Semi-empirical/DefaultSpin/AM1/Charge 0/Spin Singlet” method. Subsequently, an energycalculation is effected on the basis of the optimized geometry. This isdone using the “TD-SFC/DFT/Default Spin/B3PW91” method with the“6-31G(d)” basis set (charge 0, spin singlet). The HOMO energy level HEhor LUMO energy level LEh is obtained from the energy calculation inHartree units. This is used to determine the HOMO and LUMO energy levelsin electron volts, calibrated by cyclic voltammetry measurements, asfollows:

HOMO(eV)=((HEh*27.212)−0.9899)/1.1206

LUMO(eV)=((LEh*27.212)−2.0041)/1.385

These values are to be regarded as HOMO and LUMO energy levels of thematerials in the context of this application.

The lowest triplet state Ti is defined as the energy of the tripletstate having the lowest energy, which is apparent from thequantum-chemical calculation described.

The lowest excited singlet state S₁ is defined as the energy of theexcited singlet state having the lowest energy, which is apparent fromthe quantum-chemical calculation described.

Further preferably, the electron transport group is characterized inthat the electron mobility μ⁻ is 10⁻⁶ cm²/(Vs) or more, very preferably10⁻⁵ cm²/(Vs) or more and most preferably 10⁻⁴ cm²/(Vs) or more.

In the compounds of formula (1), the LUMO is preferably localized to theelectron transport group. It is very preferable when the LUMO is morethan 80% localized on the electron-transporting group, and even morepreferable when the LUMO is not localized on the LTG (for example anamine or carbazole group) at all. It is especially preferred when theHOMO and LUMO of the compound of the invention do not overlap at all.The person skilled in the art has no difficulties at all in determiningthe overlap of the orbitals. For this purpose, the calculation methodspecified herein is used and orbitals having a probability density of90% are assumed. The overlap can be calculated by determining overlapintegrals.

The hole transport group preferably has a HOMO energy (HOMO_(LTG))within the range of the electron work function of the anode used(ϕ_(anode)) plus+1.5 eV or less, i.e.:

HOMO_(LTG)≤(ϕ_(anode)+1.5 eV)

When the anode used has an electron work function of −5 eV, the HOMOenergy of the hole transport group is −3.5 eV or less (i.e. morenegative than −3.5 eV). It is very preferable when the hole transportgroup has a HOMO energy equal to or less than the electron work functionof the anode, most preferably less.

Further preferably, the hole transport group is characterized in thatthe hole mobility μ₊ is 10⁻⁶ cm²/(Vs) or more, very preferably 10⁻⁵cm²/(Vs) or more and most preferably 10⁻⁴ cm²/(Vs) or more.

In the compounds of formula (1), the HOMO is significantly localized onthe hole transport group. “Significantly” means here that the HOMO islocalized on the hole-conducting group to an extent of 80% or more or isnot localized on the electron-deficient electron-transporting group.

Preferably, the LTG is a group of the following general formulae, wherethe positions indicated by the dotted bond are the joining positions toAr¹ or Ar² and where the groups may be substituted by one or more R¹radicals which may be the same or different at each instance:

where:

-   Ar⁴ is the same or different at each instance and is selected from    aryl or heteroaryl groups which have 6 to 13 aromatic ring atoms and    may be substituted by one or more R¹ radicals;-   Ar⁵ is the same or different at each instance and is selected from    aryl or heteroaryl groups which have 6 to 13 aromatic ring atoms and    may be substituted by one or more R¹ radicals;-   X² is the same or different at each instance and is selected from    C(R²)₂, Si(R²)₂, C═O, O, S, S═O, SO₂ and NR²-   Y is a single bond;-   n is the same or different at each instance and is 0, 1, 2, 3 or 4;-   i is the same or different at each instance and is 0 or 1;-   k is the same or different at each instance and is 0 or 1, where at    least one index k per group has to be 1;

and where the above definitions otherwise apply.

Particularly preferred groups of the formula (L-1) are those of thefollowing formulae (L-5) to (L-10):

where the symbols that occur are defined as specified above. Thepreferred embodiments of groups specified in the application arelikewise considered to be preferred.

Particularly preferred groups of the formula (L-2) are those of thefollowing formulae (L-11) to (L-12):

where the symbols that occur are defined as specified above. Thepreferred embodiments of groups specified in the application arelikewise considered to be preferred.

It is especially preferable that, in the formulae (L-11) to (L-12), Ar⁴is the same or different and is selected from phenyl, naphthyl, pyridyl,pyrimidyl, pyridazyl, pyrazinyl and triazinyl, each of which may besubstituted by one or more R² radicals. It is further preferable thatthe X group is the same or different at each instance and is selectedfrom C(R²)₂, C═O, O, S and NR².

Particular preference is given to the formula (L-11).

Particularly preferred groups of the formula (L-3) are those of thefollowing formulae:

where the symbols that occur are as defined above. The preferredembodiments of groups specified in the application are likewiseconsidered to be preferred.

It is especially preferable that, in the formulae (L-13) to (L-16), Ar⁴and Ar⁵ are the same or different and are selected from phenyl,naphthyl, pyridyl, pyrimidyl, pyridazyl, pyrazinyl and triazinyl, eachof which may be substituted by one or more R² radicals.

Particularly preferred groups of the formula (L-4) are those of thefollowing formula:

where Ar⁴ is the same or different and is selected from phenyl,naphthyl, pyridyl, pyrimidyl, pyridazyl, pyrazinyl and triazinyl, eachof which may be substituted by one or more R² radicals.

It is especially preferable that, in the formulae (L-5) to (L-10), Ar⁴and Ar⁵ are the same or different and are selected from phenyl,naphthyl, pyridyl, pyrimidyl, pyridazyl, pyrazinyl and triazinyl, eachof which may be substituted by one or more R² radicals. It is furtherpreferable that the X² group is the same or different at each instanceand is selected from C(R²)₂, C═O, O, S and NR².

Particular preference is given to the formulae (L-5) and (L-6).

Examples of very particularly preferred LTGs having R¹ radicals are thefollowing groups which may be substituted by one or more independent R²radicals, where the dotted bonds indicate the binding positions to theAr¹ and Ar² groups.

The compounds of the invention may be prepared according to schemes 1and 2.

The corresponding monoboronic acids (a) can be prepared by Suzukicoupling and subsequent silylation (scheme 1). A further option is toprepare the corresponding monoboronic acids proceeding from themonobromides by Buchwald coupling and subsequent silylation (scheme 2).The reaction of these monoboronic acids via Suzuki coupling withappropriate aryl bromides or aryl chlorides leads to the targetcompounds.

where the above-specified definitions and the preferred embodimentsthereof apply to the indices and symbols used.

where the G³-N_(p/s)—H group is the G² group and where the G² groupcontains a primary (p) or secondary (s) amine and is an LTG. The G¹group in this case is an ETG. In addition, p is 1. The above-specifieddefinitions and the preferred embodiments thereof apply to the otherindices and symbols used.

The Suzuki and Buchwald reactions are well-known to those skilled in theart, who will not have any difficulties in applying the reactions andknown variations thereof to the compounds of the invention, in order toprepare them in the range claimed, taking account of common knowledge inthe art. Furthermore, both in the Suzuki reaction and in the Buchwaldreaction, the chemical functionalities can be exchanged between thesubstituent and the structure containing the A and A′ rings. This meansthat the substituent containing G¹ or G² may also contain the boronicacid, whereas the structure containing the rings A and A′ contains thehalide. The schemes which follow illustrate the application of theprocesses mentioned by way of example using more specific cases, wherethe above definitions apply to the symbols and indices used. The Argroups in the schemes which follow are the same or different at eachinstance and represent aromatic or heteroaromatic groups which may beselected in such a way that the above definitions for ETG, LTG andgenerally those of formula (1) are satisfied. Hal represents halides ispreferably Br or I.

where the group containing the N(Ar₃) unit is the LTG and the othergroup is the ETG.

A further option for preparation of the compounds of the invention isthat of reacting a dihalide (Hal=Br, I) with 1 eq of the correspondingboronic acid and subsequent Suzuki coupling to give the desired product,the synthesis procedure making use of similar steps to those shown inscheme 1.

A further option is the reaction of the dihalide with 2 eq of theboronic acid of the ETG.

Many of the dihalides (a) or diboronic acids (b) are commerciallyavailable or can be synthesized as specified in scheme 6. They cansubsequently be converted to the desired products via Suzuki couplings.

A further option for preparation of compounds of the invention is thatof converting carbazole derivatives, followed by an Ullmann or Buchwaldcoupling.

The processes shown for synthesis of the compounds of the inventionshould be understood by way of example. The person skilled in the artwill be able to develop alternative synthesis routes within the scope ofhis common knowledge in the art.

The overview which follows contains an illustration of compounds of theinvention which can be prepared by one of the processes describedherein.

The invention further provides for the use of a compound of the formula(1) in an electronic device, preferably in an electron-transportinglayer and/or in an emitting layer.

The electronic device of the invention is preferably selected from thegroup consisting of organic integrated circuits (OICs), organicfield-effect transistors (OFETs), organic thin-film transistors (OTFTs),organic light-emitting transistors (OLETs), organic solar cells (OSCs),organic optical detectors, organic photoreceptors, organic field-quenchdevices (OFQDs), organic light-emitting electrochemical cells (OLECs,LECs or LEECs), organic laser diodes (O-lasers) and organiclight-emitting diodes (OLEDs). Particular preference is given to theorganic electroluminescent devices, very particular preference to theOLECs and OLEDs and especial preference to the OLEDs.

The organic layer comprising the compound of the formula (1) ispreferably a layer having an electron-transporting function. It is morepreferably an electron injection layer, electron transport layer, holeblocker layer or emitting layer.

In a very particularly preferred embodiment, both G¹ and G² in thecompound of the formula (1) are ETGs and the compounds of the formula(1) in that case are most preferably in a layer of an aforementionedelectronic device having an electron-transporting function, and thecompound is especially preferably in an electron injection layer (EIL),electron transport layer (ETL), hole blocker layer (HBL) or emittinglayer, an EIL and ETL being especially preferable and an ETL even morepreferable.

In a further very particularly preferred embodiment, one of the two G¹and G² groups in the compound of the formula (1) is an LTG and the othergroup is an ETG and the compound of the formula (1) in that case is mostpreferably in a layer of an aforementioned electronic device having anelectron-transporting function, and the compound is especiallypreferably in an electron injection layer, electron transport layer,hole blocker layer or emitting layer, it being even more preferable whenthis compound is present in an emitting layer, especially as matrixmaterial.

A hole transport layer according to the present application is a layerhaving a hole-transporting function between the anode and emittinglayer.

An electron transport layer according to the present application is alayer having an electron-transporting function between the cathode andemitting layer.

Hole injection layers and electron blocker layers are understood in thecontext of the present application to be specific embodiments of holetransport layers. A hole injection layer, in the case of a plurality ofhole transport layers between the anode and emitting layer, is a holetransport layer which directly adjoins the anode or is separatedtherefrom only by a single coating of the anode. An electron blockerlayer, in the case of a plurality of hole transport layers between theanode and emitting layer, is that hole transport layer which directlyadjoins the emitting layer on the anode side.

As already mentioned above, the compound of the formula (1), in apreferred embodiment, is used as matrix material in an emission layer ofan organic electronic device, especially in an organicelectroluminescent device, for example in an OLED or OLEC. In this case,the matrix material of the formula (1) is present in the electronicdevice in combination with one or more dopants, preferablyphosphorescent dopants.

The term “phosphorescent dopants” typically encompasses compounds wherethe emission of light is effected through a spin-forbidden transition,for example a transition from an excited triplet state or a state havinga higher spin quantum number, for example a quintet state.

Suitable phosphorescent dopants are especially compounds which, whensuitably excited, emit light, preferably in the visible region, and alsocontain at least one atom of atomic number greater than 20, preferablygreater than 38, and less than 84, more preferably greater than 56 andless than 80. Preference is given to using, as phosphorescent dopants,compounds containing copper, molybdenum, tungsten, rhenium, ruthenium,osmium, rhodium, iridium, palladium, platinum, silver, gold or europium,especially compounds containing iridium, platinum or copper.

In the context of the present application, all luminescent iridium,platinum or copper complexes are considered to be phosphorescentcompounds. Examples of phosphorescent dopants are adduced in a sectionwhich follows.

A dopant in a system comprising a matrix material and a dopant isunderstood to mean that component having the smaller proportion in themixture. Correspondingly, a matrix material in a system comprising amatrix material and a dopant is understood to mean that component havingthe greater proportion in the mixture.

The proportion of the matrix material in the emitting layer in this caseis between 50.0% and 99.9% by volume, preferably between 80.0% and 99.5%by volume, and more preferably between 92.0% and 99.5% by volume forfluorescent emitting layers and between 85.0% and 97.0% by volume forphosphorescent emitting layers.

Correspondingly, the proportion of the dopant is between 0.1% and 50.0%by volume, preferably between 0.5% and 20.0% by volume, and morepreferably between 0.5% and 8.0% by volume for fluorescent emittinglayers and between 3.0% and 15.0% by volume for phosphorescent emittinglayers.

An emitting layer of an organic electroluminescent device may alsocomprise systems comprising a plurality of matrix materials (mixedmatrix systems) and/or a plurality of dopants. In this case too, thedopants are generally those materials having the smaller proportion inthe system and the matrix materials are those materials having thegreater proportion in the system. In individual cases, however, theproportion of a single matrix material in the system may be less thanthe proportion of a single dopant.

In a further preferred embodiment of the invention, the compounds offormula (1) are used as a component of mixed matrix systems. The mixedmatrix systems preferably comprise two or three different matrixmaterials, more preferably two different matrix materials. Preferably,in this case, one of the two materials is a material havinghole-transporting properties and the other material is a material havingelectron-transporting properties. The desired electron-transporting andhole-transporting properties of the mixed matrix components may,however, also be combined mainly or entirely in a single mixed matrixcomponent, in which case the further mixed matrix component(s) fulfil(s)other functions. The two different matrix materials may be present in aratio of 1:50 to 1:1, preferably 1:20 to 1:1, more preferably 1:10 to1:1 and most preferably 1:4 to 1:1. Preference is given to using mixedmatrix systems in phosphorescent organic electroluminescent devices. Onesource of more detailed information about mixed matrix systems is theapplication WO 2010/108579.

Particularly suitable matrix materials which can be used in combinationwith the inventive compounds as matrix components of a mixed matrixsystem are selected from the preferred matrix materials specified belowfor phosphorescent dopants or the preferred matrix materials forfluorescent dopants, according to what type of dopant is used in themixed matrix system.

The present invention therefore also relates to a composition comprisingat least one compound of formula (1) and at least one further matrixmaterial.

The present invention also relates to a composition comprising at leastone compound of formula (1) and at least one wide band gap material, awide band gap material being understood to mean a material in the senseof the disclosure of U.S. Pat. No. 7,294,849. These systems exhibitparticularly advantageous performance data in electroluminescentdevices.

The present invention further relates to a composition comprising atleast one compound of formula (1) and at least one further organicsemiconductor material selected from the group consisting of fluorescentemitters, phosphorescent emitters, host materials, matrix materials,electron transport materials, electron injection materials, holeconductor materials, hole injection materials, electron blockermaterials and hole blocker materials.

Preferred phosphorescent dopants for use in mixed matrix systems are thepreferred phosphorescent dopants specified hereinafter.

Examples of phosphorescent dopants can be found in applications WO2000/70655, WO 2001/41512, WO 2002/02714, WO 2002/15645, EP 1191613, EP1191612, EP 1191614, WO 2005/033244, WO 2005/019373 and US 2005/0258742.In general, all phosphorescent complexes as used for phosphorescentOLEDs according to the prior art and as known to those skilled in theart in the field of organic electroluminescent devices are suitable foruse in the inventive devices.

Explicit examples of phosphorescent dopants are adduced in the followingtable:

Preferred fluorescent dopants are selected from the class of thearylamines. An arylamine or an aromatic amine in the context of thisinvention is understood to mean a compound containing three substitutedor unsubstituted aromatic or heteroaromatic ring systems bonded directlyto the nitrogen. Preferably, at least one of these aromatic orheteroaromatic ring systems is a fused ring system, more preferablyhaving at least 14 aromatic ring atoms. Preferred examples of these arearomatic anthracenamines, aromatic anthracenediamines, aromaticpyrenamines, aromatic pyrenediamines, aromatic chrysenamines or aromaticchrysenediamines. An aromatic anthracenamine is understood to mean acompound in which a diarylamino group is bonded directly to ananthracene group, preferably in the 9 position. An aromaticanthracenediamine is understood to mean a compound in which twodiarylamino groups are bonded directly to an anthracene group,preferably in the 9,10 positions. Aromatic pyrenamines, pyrenediamines,chrysenamines and chrysenediamines are defined analogously, where thediarylamino groups in the pyrene are bonded preferably in the 1 positionor 1,6 positions. Further preferred dopants are indenofluorenamines or-fluorenediamines, for example according to WO 2006/108497 or WO2006/122630, benzoindenofluorenamines or -fluorenediamines, for exampleaccording to WO 2008/006449, and dibenzoindenofluorenamines or-fluorenediamines, for example according to WO 2007/140847, and theindenofluorene derivatives having fused aryl groups disclosed in WO2010/012328.

Useful matrix materials, preferably for fluorescent dopants, as well asthe compounds of the formula (1), are materials from various substanceclasses. Preferred matrix materials are selected from the classes of theoligoarylenes (e.g. 2,2′,7,7′-tetraphenylspirobifluorene according to EP676461 or dinaphthylanthracene), especially of the oligoarylenescontaining fused aromatic groups, the oligoarylenevinylenes (e.g. DPVBior spiro-DPVBi according to EP 676461), the polypodal metal complexes(for example according to WO 2004/081017), the hole-conducting compounds(for example according to WO 2004/058911), the electron-conductingcompounds, especially ketones, phosphine oxides, sulfoxides, etc. (forexample according to WO 2005/084081 and WO 2005/084082), theatropisomers (for example according to WO 2006/048268), the boronic acidderivatives (for example according to WO 2006/117052) or thebenzanthracenes (for example according to WO 2008/145239). Particularlypreferred matrix materials are selected from the classes of theoligoarylenes comprising naphthalene, anthracene, benzanthracene and/orpyrene or atropisomers of these compounds, the oligoarylenevinylenes,the ketones, the phosphine oxides and the sulfoxides. Very particularlypreferred matrix materials are selected from the classes of theoligoarylenes comprising, anthracene, benzanthracene, benzophenanthreneand/or pyrene or atropisomers of these compounds. An oligoarylene in thecontext of this invention shall be understood to mean a compound inwhich at least three aryl or arylene groups are bonded to one another.

Preferred matrix materials for phosphorescent dopants are, as well asthe compounds of the formula (1), aromatic amines, especiallytriarylamines, for example according to US 2005/0069729, carbazolederivatives (e.g. CBP, N,N-biscarbazolylbiphenyl) or compounds accordingto WO 2005/039246, US 2005/0069729, JP 2004/288381, EP 1205527 or WO2008/086851, bridged carbazole derivatives, for example according to WO2011/088877 and WO 2011/128017, indenocarbazole derivatives, for exampleaccording to WO 2010/136109 and WO 2011/000455, azacarbazolederivatives, for example according to EP 1617710, EP 1617711, EP1731584, JP 2005/347160, indolocarbazole derivatives, for exampleaccording to WO 2007/063754 or WO 2008/056746, ketones, for exampleaccording to WO 2004/093207 or WO 2010/006680, phosphine oxides,sulfoxides and sulfones, for example according to WO 2005/003253,oligophenylenes, bipolar matrix materials, for example according to WO2007/137725, silanes, for example according to WO 2005/111172,azaboroles or boronic esters, for example according to WO 2006/117052,triazine derivatives, for example according to WO 2010/015306, WO2007/063754 or WO 2008/056746, zinc complexes, for example according toEP 652273 or WO 2009/062578, aluminum complexes, e.g. BAlq, diazasilolederivatives and tetraazasilole derivatives, for example according to WO2010/054729, diazaphosphole derivatives, for example according to WO2010/054730, and aluminum complexes, e.g. BAlQ.

Apart from the cathode, anode and the layer comprising the compound ofthe formula (1), the electronic device may comprise further layers.These are selected, for example, from in each case one or more holeinjection layers, hole transport layers, hole blocker layers, emittinglayers, electron transport layers, electron injection layers, electronblocker layers, exciton blocker layers, interlayers, charge generationlayers (IDMC 2003, Taiwan, Session 21 OLED (5), T. Matsumoto, T. Nakada,J. Endo, K. Mori, N. Kawamura, A. Yokoi, J. Kido, Multiphoton Organic ELDevice Having Charge Generation Layer) and/or organic or inorganic p/njunctions. However, it should be pointed out that not necessarily everyone of these layers need be present.

The sequence of layers in the organic electroluminescent device ispreferably as follows:

anode-hole injection layer-hole transport layer-emitting layer-electrontransport layer-electron injection layer-cathode.

At the same time, it should be pointed out again that not all the layersmentioned need be present and/or that further layers may additionally bepresent.

The inventive organic electroluminescent device may contain two or moreemitting layers. More preferably, these emission layers in this casehave several emission maxima between 380 nm and 750 nm overall, suchthat the overall result is white emission; in other words, variousemitting compounds which may fluoresce or phosphoresce and which emitblue or yellow or orange or red light are used in the emitting layers.Especially preferred are three-layer systems, i.e. systems having threeemitting layers, where the three layers show blue, green and orange orred emission (for the basic construction see, for example, WO2005/011013). It should be noted that, for the production of whitelight, rather than a plurality of color-emitting emitter compounds, anemitter compound used individually which emits over a broad wavelengthrange may also be suitable.

Suitable charge transport materials as usable in the hole injection orhole transport layer or electron blocker layer or in the electrontransport layer of the organic electroluminescent device of theinvention are, for example, the compounds disclosed in Y. Shirota etal., Chem. Rev. 2007, 107(4), 953-1010, or other materials as used inthese layers according to the prior art.

Materials used for the electron transport layer may be any materials asused according to the prior art as electron transport materials in theelectron transport layer. Especially suitable are aluminium complexes,for example Alq₃, zirconium complexes, for example Zrq₄, benzimidazolederivatives, triazine derivatives, pyrimidine derivatives, pyridinederivatives, pyrazine derivatives, quinoxaline derivatives, quinolinederivatives, oxadiazole derivatives, aromatic ketones, lactams, boranes,diazaphosphole derivatives and phosphine oxide derivatives. Furthersuitable materials are derivatives of the abovementioned compounds asdisclosed in JP 2000/053957, WO 2003/060956, WO 2004/028217, WO2004/080975 and WO 2010/072300.

As hole transport materials are especially preferably materials whichcan be used in a hole transport, hole injection or electron blockerlayer, indenofluorenamine derivatives (for example according to WO06/122630 or WO 06/100896), the amine derivatives disclosed in EP1661888, hexaazatriphenylene derivatives (for example according to WO01/049806), amine derivatives having fused aromatic systems (for exampleaccording to U.S. Pat. No. 5,061,569), the amine derivatives disclosedin WO 95/09147, monobenzoindenofluorenamines (for example according toWO 08/006449), dibenzoindenofluorenamines (for example according to WO07/140847), spirobifluorenamines (for example according to WO2012/034627 or the as yet unpublished EP 12000929.5), fluorenamines (forexample according to the as yet unpublished applications EP 12005369.9,EP 12005370.7 and EP 12005371.5), spirodibenzopyranamines (for exampleaccording to the as yet unpublished application EP 11009127.9) anddihydroacridine derivatives (for example according to the as yetunpublished EP 11007067.9).

Preferred cathodes of the electronic device are metals having a low workfunction, metal alloys or multilayer structures composed of variousmetals, for example alkaline earth metals, alkali metals, main groupmetals or lanthanoids (e.g. Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.).Additionally suitable are alloys composed of an alkali metal or alkalineearth metal and silver, for example an alloy composed of magnesium andsilver. In the case of multilayer structures, in addition to the metalsmentioned, it is also possible to use further metals having a relativelyhigh work function, for example Ag or Al, in which case combinations ofthe metals such as Ca/Ag, Mg/Ag or Ba/Ag, for example, are generallyused. It may also be preferable to introduce a thin interlayer of amaterial having a high dielectric constant between a metallic cathodeand the organic semiconductor. Examples of useful materials for thispurpose are alkali metal or alkaline earth metal fluorides, but also thecorresponding oxides or carbonates (e.g. LiF, Li₂O, BaF₂, MgO, NaF, CsF,Cs₂CO₃, etc.). It is also possible to use lithium quinolinate (LiQ) forthis purpose. The layer thickness of this layer is preferably between0.5 and 5 nm.

Preferred anodes are materials having a high work function. Preferably,the anode has a work function of greater than 4.5 eV versus vacuum.Firstly, metals having a high redox potential are suitable for thispurpose, for example Ag, Pt or Au. Secondly, metal/metal oxideelectrodes (e.g. Al/Ni/NiO_(x), Al/PtO_(x)) may also be preferable. Forsome applications, at least one of the electrodes has to be transparentor partly transparent in order to enable the irradiation of the organicmaterial (organic solar cell) or the emission of light (OLED, O-LASER).Preferred anode materials here are conductive mixed metal oxides.Particular preference is given to indium tin oxide (ITO) or indium zincoxide (IZO). Preference is further given to conductive doped organicmaterials, especially conductive doped polymers. In addition, the anodemay also consist of two or more layers, for example of an inner layer ofITO and an outer layer of a metal oxide, preferably tungsten oxide,molybdenum oxide or vanadium oxide.

The electronic device, in the course of production, is appropriately(according to the application) structured, contact-connected and finallysealed, since the lifetime of the devices of the invention is shortenedin the presence of water and/or air.

In a preferred embodiment, the electronic device of the invention ischaracterized in that one or more layers are coated by a sublimationprocess. In this case, the materials are applied by vapor deposition invacuum sublimation systems at an initial pressure of less than 10⁻⁵mbar, preferably less than 10⁻⁶ mbar. In this case, however, it is alsopossible that the initial pressure is even lower, for example less than10⁻⁷ mbar.

Preference is likewise given to an organic electroluminescent device,characterized in that one or more layers are coated by the OVPD (organicvapor phase deposition) method or with the aid of a carrier gassublimation. In this case, the materials are applied at a pressurebetween 10⁻⁵ mbar and 1 bar. A special case of this method is the OVJP(organic vapour jet printing) method, in which the materials are applieddirectly by a nozzle and thus structured (for example M. S. Arnold etal., Appl. Phys. Lett. 2008, 92, 053301).

Preference is additionally given to an organic electroluminescentdevice, characterized in that one or more layers are produced fromsolution, for example by spin-coating, or by any printing method, forexample screen printing, flexographic printing, nozzle printing oroffset printing, but more preferably LITI (light-induced thermalimaging, thermal transfer printing) or inkjet printing. For thispurpose, soluble compounds of formula (1) are needed. High solubilitycan be achieved by suitable substitution of the compounds.

It is further preferable that an organic electroluminescent device ofthe invention is produced by applying one or more layers from solutionand one or more layers by a sublimation method.

The invention thus further provides a process for producing theelectronic device of the invention, characterized in that at least oneorganic layer is applied by gas phase deposition or from solution.

According to the invention, the electronic devices comprising one ormore compounds of formula (1) can be used in displays, as light sourcesin lighting applications and as light sources in medical and/or cosmeticapplications (e.g. light therapy).

The present invention also relates to a formulation comprising at leastone compound of formula (1) or at least one of the abovementionedcompositions and at least one solvent.

Suitable and preferred solvents are, for example, toluene, anisole, o-,m- or p-xylene, methyl benzoate, mesitylene, tetralin, veratrole, THF,methyl-THF, THP, chlorobenzene, dioxane, phenoxytoluene, especially3-phenoxytoluene, (−)-fenchone, 1,2,3,5-tetramethylbenzene,1,2,4,5-tetramethylbenzene, 1-methylnaphthalene, 2-methylbenzothiazole,2-phenoxyethanol, 2-pyrrolidinone, 3-methylanisole, 4-methylanisole,3,4-dimethylanisole, 3,5-dimethylanisole, acetophenone, α-terpineol,benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone,cyclohexylbenzene, decalin, dodecylbenzene, ethyl benzoate, indane,methyl benzoate, NMP, p-cymene, phenetole, 1,4-diisopropylbenzene,dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycolbutyl methyl ether, diethylene glycol dibutyl ether, triethylene glycoldimethyl ether, diethylene glycol monobutyl ether, tripropylene glycoldimethyl ether, tetraethylene glycol dimethyl ether,2-isopropylnaphthalene, pentylbenzene, hexylbenzene, heptylbenzene,octylbenzene, 1,1-bis(3,4-dimethylphenyl)ethane or mixtures of thesesolvents.

Devices comprising the compounds of formula (1) can be used in a widevariety of ways. For example, it is possible to use electroluminescentdevices comprising one or more compounds of formula (1) in displays fortelevisions, mobile phones, computers and cameras. The devices mayalternatively be used in lighting applications. In addition,electroluminescent devices can be utilized, for example, in OLEDs orOLECs comprising at least one of the compounds of formula (1) inmedicine or cosmetics for phototherapy. It is thus possible to treat amultitude of disorders (psoriasis, atopic dermatitis, inflammation,acne, skin cancer etc.) or to avoid and reduce formation of skinwrinkles, skin reddening and skin aging. In addition, the light-emittingdevices can be used to keep drinks or food fresh, or in order tosterilize devices (for example medical devices).

The present invention therefore provides an electronic device,preferably an organic electroluminescent device, very preferably an OLEDor OLEC and most preferably an OLED, comprising at least one compound offormula (1) for use in medicine for phototherapy.

The present invention further preferably relates to an electronicdevice, preferably an organic electroluminescent device, very preferablyan OLED or OLEC and most preferably an OLED, comprising at least onecompound of formula (1) for use for phototherapeutic treatment of skindiseases.

The present invention further very preferably relates to an electronicdevice, preferably an organic electroluminescent device, very preferablyan OLED or OLEC and most preferably an OLED, comprising at least onecompound of formula (1) for use for phototherapeutic treatment ofpsoriasis, atopic dermatitis, inflammation disorders, vitiligo, woundhealing and skin cancer.

The present invention further relates to the use of the electronicdevice, preferably an organic electroluminescent device, very preferablyan OLED or OLEC and most preferably an OLED, comprising at least onecompound of formula (1) in cosmetics, preferably for treatment of acne,skin aging and cellulite.

The compounds of the invention and the organic electroluminescentdevices of the invention feature the following surprising advantagesover the prior art:

-   1. The compounds of the invention are of very good suitability for    use in an emission layer and exhibit improved performance data over    compounds from the prior art.-   2. The compounds of the invention have a relatively low sublimation    temperature and high thermal stability, and can therefore be    sublimed without decomposition or residue. In addition, they have    high oxidation stability and a high glass transition temperature,    which is advantageous for processibility, for example from solution    or from the gas phase, and also for use in electronic devices.-   3. The use of the compounds of the invention in electronic devices,    especially used as electron transport or electron injection    material, but also as matrix material, leads to high efficiencies,    low operating voltages and long lifetimes.

It should be pointed out that variations of the embodiments described inthe present invention are covered by the scope of this invention. Anyfeature disclosed in the present invention may, unless this isexplicitly ruled out, be exchanged for alternative features which servethe same purpose or an equivalent or similar purpose. Thus, any featuredisclosed in the present invention, unless stated otherwise, should beconsidered as an example from a generic series or as an equivalent orsimilar feature.

All features of the present invention may be combined with one anotherin any manner, unless particular features and/or steps are mutuallyexclusive. This is especially true of preferred features of the presentinvention.

Equally, features of non-essential combinations may be used separately(and not in combination).

It should also be pointed out that many of the features, and especiallythose of the preferred embodiments of the present invention, arethemselves inventive and should not be regarded merely as some of theembodiments of the present invention. For these features, independentprotection may be sought in addition to or as an alternative to anycurrently claimed invention.

The technical teaching disclosed with the present invention may beabstracted and combined with other examples.

The invention is illustrated in detail by the examples which follow,without any intention of restricting it thereby.

EXAMPLES

The syntheses which follow, unless stated otherwise, are conducted undera protective gas atmosphere in dried solvents. The solvents and reagentscan be purchased, for example, from Sigma-ALDRICH or ABCR. The figuresin square brackets for chemical compounds known from the literature arethe CAS number.

Example 1 Synthesis of 3-dibenzofuran-4-yl-9-phenyl-9H-carbazole

28.9 g (136 mmol) of dibenzofuran-4-boronic acid, 40 g (124.1 mmol) of3-bromo-9-phenyl-9H-carbazole and 78.9 mL (158 mmol) of Na₂CO₃ (2 Msolution) are suspended in 120 mL of toluene, 120 mL of ethanol and 100mL of water. 2.6 g (2.2 mmol) of Pd(PPh₃)₄ are added to this suspension,and the reaction mixture is heated under reflux for 16 h. After cooling,the organic phase is removed, filtered through silica gel, washed threetimes with 200 mL of water and then concentrated to dryness. The residueis recrystallized from toluene. The yield is 49.7 g (121 mmol),corresponding to 97% of theory.

In an analogous manner, it is possible to obtain the followingcompounds:

Reactant 1 Reactant 2 Product Yield

90%

92%

89%

92%

86%

69%

72%

Example 2 Synthesis of bis(biphenyl-4-yl)dibenzofuran-4-ylamine

A degassed solution of 36.6 g (147 mmol) of 4-bromodibenzofuran and 39.5g (123 mmol) of bis(biphenyl-4-yl)amine in 600 mL of toluene issaturated with N₂ for 1 h. Added to the solution thereafter are first2.09 mL (8.6 mmol) of P(tBu)₃, then 1.38 g (6.1 mmol) of palladium(II)acetate, and then 17.7 g (185 mmol) of NaOtBu in the solid state. Thereaction mixture is heated under reflux for 1 h. After cooling to roomtemperature, 500 mL of water are added cautiously The aqueous phase iswashed with 3×50 mL of toluene, dried over M_(g)SO₄, and the solvent isremoved under reduced pressure. Thereafter, the crude product ispurified by chromatography using silica gel with heptane/ethyl acetate(20:1).

The yield is 57.7 g (118 mmol), corresponding to 80% of theory.

In an analogous manner, it is possible to obtain the followingcompounds:

Reactant 1 Reactant 2 Product Yield

90%

87%

83%

57%

93%

Example 3 Synthesis of9-phenyl-3-(6-trimethylsilanyldibenzofuran-4-yl)-9H-carbazole

To a solution, cooled to 20° C., of 49 g (121 mmol) of3-dibenzofuran-4-yl-9-phenyl-9H-carbazole and 28 g (242 mmol) of TMEDAin 1000 mL of THE are added dropwise 127 mL (225.4 mmol) ofn-butyllithium (2.5 M in hexane). The reaction mixture is stirred atroom temperature for 3 h, then cooled down to 0° C., and 26 g (242 mmol)of chlorotrimethylsilane are added dropwise within 30 minutes and themixture is stirred at room temperature for 8 h. Subsequently, thesolvent is removed under reduced pressure and the residue is purified bychromatography using silica gel with chloroform as eluent. Yield: 34 g(72 mmol), 60% of theory.

In an analogous manner, it is possible to obtain the followingcompounds:

Reactant 1 Product Yield

81%

83%

88%

84%

88%

70%

86%

79%

75%

72%

65%

64%

63%

Example 4 Synthesis ofB-[6-(phenyl-9H-carbazol-3-yl)-4-dibenzofuranyl]boronic acid

Under protective gas, 21 g (86 mmol) of bromine tribromide are addeddropwise to a solution of 34 g (72 mmol) ofN-phenyl-3-(6-trimethylsilanyldibenzofuran-4-yl)-9H-carbazole in 500 mLof dichloromethane and the mixture is stirred at room temperature for 10h. Thereafter, a little water is added gradually to the mixture and theprecipitated residue is filtered off and washed with heptane. The yieldis 28 g (62 mmol), corresponding to 86% of theory.

In an analogous manner, it is possible to obtain the followingcompounds:

Reactant 1 Product Yield

84%

84%

81%

87%

86%

79%

78%

83%

85%

81%

78%

69%

78%

78%

Example 5 Synthesis ofB-[6-(phenyl-9H-carbazol-3-yl)-4-dibenzofuranyl]boronic acid

9 g (32 mmol) of B,B′-4,6-dibenzofurandiylbisboronic acid, 15 g (31.6mmol) of 3-bromo-9-phenyl-9H-carbazole and 31 mL (63 mmol) of Na₂CO₃ (2M solution) are suspended in 120 mL of toluene and 120 mL of ethanol.0.73 g (0.63 mmol) of Pd(PPh₃)₄ are added to this suspension, and thereaction mixture is heated under reflux for 16 h. After cooling, theorganic phase is removed, filtered through silica gel, washed threetimes with 200 mL of water and then concentrated to dryness. The residueis recrystallized from toluene. The yield is 11.1 g (24 mmol),corresponding to 70% of theory.

In an analogous manner, it is possible to obtain the followingcompounds:

Reactant 1 Reactant 2 Product Yield

85%

69%

74%

Example 6 Synthesis of3-(6-bromodibenzofuran-4-yl)-9-phenyl-9H-carbazole

10.43 g (32 mmol) of B-(9-phenyl-9H-carbazol-3-yl)boronic acid, 8.9 g(31.6 mmol) of 4,6-dibromodibenzofuran and 31 mL (63 mmol) of Na₂CO₃ (2M solution) are suspended in 120 mL of toluene and 120 mL of ethanol.0.73 g (0.63 mmol) of Pd(PPh₃)₄ is added to this suspension, and thereaction mixture is heated under reflux for 16 h. After cooling, theorganic phase is removed, filtered through silica gel, washed threetimes with 200 mL of water and then concentrated to dryness. The residueis recrystallized from toluene. The yield is 11.4 g (23 mmol),corresponding to 73% of theory.

In an analogous manner, it is possible to obtain the followingcompounds:

Reactant 1 Reactant 2 Product Yield

51%

65%

69%

67%

62%

62%

61%

64%

66%

56%

In an analogous manner, it is also possible to obtain the followingcompounds by a second addition with the appropriate boronic acids: Theresidue is recrystallized from toluene and finally sublimed under highvacuum (p=5×10⁻⁵ mbar).

Reactant 1 Reactant 2 Product Yield

80%

79%

68%

78%

87%

89%

87%

83%

80%

79%

79%

Example 7 Synthesis of3-{6-[3-(4,6-diphenyl-[1,3,5]triazin-2-yl)phenyl]dibenzofuran-4-yl}-9-phenyl-9H-carbazole

32.1 g (70 mmol) ofB-[6-(phenyl-9H-carbazol-3-yl)-4-dibenzofuranyl]boronic acid, 27 g (70mmol) of 2-(3-bromophenyl)-4,6-diphenyl-[1,3,5]triazine and 78.9 mL (158mmol) of Na₂CO₃ (2 M solution) are suspended in 120 mL of ethanol and100 mL of water. 1.3 g (1.1 mmol) of Pd(PPh₃)₄ are added to thissuspension, and the reaction mixture is heated under reflux for 16 h.After cooling, dichloromethane is added to the mixture, and the organicphase is removed and filtered through silica gel. The yield is 44 g (61mmol), corresponding to 87% of theory. The residue is recrystallizedfrom toluene and finally sublimed under high vacuum (p=5×10⁻⁵ mbar). Thepurity is 99.9%.

In an analogous manner, it is possible to obtain the followingcompounds:

Reactant 1 Reactant 2

Product Yield

79%

83%

86%

89%

80%

79%

84%

79%

77%

78%

79%

75%

74%

59%

67%

68%

70%

71%

78%

78%

73%

79%

Example 8 Synthesis of9,9′-diphenyl-8-(3-{4-phenyl-6-[(E)-((Z)-1-propenyl)-buta-1,3-dienyl]-[1,3,5]triazin-2-yl}-phenyl)-9H,9′H-[1,2′]bicarbazolyl

50 g (70.58 mmol) of8-[3-(4,6-diphenyl-[1,3,5]triazin-2-yl)-phenyl]-9′-phenyl-9H,9′H-[1,2′]bicarbazolyland 16.4 g (105.87 mmol) of bromobenzene are dissolved in toluene anddegassed by means of introduction of protective gas. This is followed byaddition of 7 mL (7 mmol, 1 M solution in toluene) oftri-tert-butylphosphine, 633.8 mg (2.82 mmol) of Pd(OAc)₂ and 10.2 g(105.87 mmol) of NaOtBu. The solids are degassed beforehand, and thereaction mixture is post-degassed and then stirred under reflux for 3 h.The warm reaction solution is filtered through Alox B (activity level1), washed with water, dried and concentrated. The yield is 42 g (53mmol), corresponding to 77% of theory. The residue is recrystallizedfrom toluene and finally sublimed under high vacuum (p=5×10⁻⁵ mbar). Thepurity is 99.9%.

In an analogous manner, it is possible to obtain the followingcompounds:

Reactant 1 Reactant 2 Product Yield

79%

80%

80%

Example 9 Synthesis of2-{6-[4-(2,6-diphenylpyridin-4-yl)phenyl]dibenzofuran-4-yl}-4,6-diphenyl[1,3,5]triazine

9 g (32 mmol) of B,B′-4,6-dibenzofurandiylbisboronic acid, 6.5 g (31.6mmol) of 2-chloro-4,6-diphenyl[1,3,5]triazine and 31 mL (63 mmol) ofNa₂CO₃ (2 M solution) are suspended in 120 mL of toluene and 120 mL ofethanol. 0.73 g (0.63 mmol) of Pd(PPh₃)₄ is added to this suspension,and the reaction mixture is heated under reflux for 8 h. Subsequently,6.5 g (31.6 mmol) of 4-(4-bromophenyl)-2,6-diphenylpyridine are addedand the mixture is heated under reflux for a further 8 h. After cooling,the organic phase is removed, filtered through silica gel, washed threetimes with 200 mL of water and then concentrated to dryness. The residueis recrystallized from toluene. The yield is 19.1 g (26 mmol),corresponding to 77% of theory.

In an analogous manner, it is possible to obtain the followingcompounds:

In the case of a symmetric compound, first 0.5 eq of reactant 2 and then0.5 eq of reactant 3 are added.

Reactant 1 Reactant 2 Reactant 3 1 eq. 0.5 eq. 0.5 eq.

Product Yield

83%

79%

69%

71%

60%

59%

65%

76%

65%

56%

61%

Example 10 Synthesis of2-{6-[4-(2,6-diphenyl-[1,3,4]triazin-4-yl)phenyl]-dibenzofuran-4-yl}-4,6-diphenyl-[1,3,5]triazinea) Preparation of2-(6-bromodibenzofuran-4-yl)-4,6-diphenyl-[1,3,5]triazine

80 g (245 mmol) of 4,6-dibromodibenzofuran are dissolved in a baked-outflask in 500 mL of dried THF. The reaction mixture is cooled to −78° C.At this temperature, 57 mL of a 1.9 M solution of n-phenyllithium indibutyl ether (115 mmol) are slowly added dropwise. The mixture isstirred at −73° C. for a further 1 hour. Subsequently, 65 g of2-chloro-4,6-diphenyl-1,3,5-triazine (245 mmol) are dissolved in 150 mLof THE and added dropwise at −70° C. After the addition has ended, thereaction mixture is warmed gradually to room temperature, stirred atroom temperature overnight, quenched with water and then concentrated ona rotary evaporator. During this time, a white solid precipitates out.The mixture is then cooled to room temperature, and the precipitatedsolid is filtered off with suction and washed with methanol. The yieldis 40 g (84 mmol), corresponding to 34% of theory.

b) Preparation of2-{6-[4-(2,6-diphenyl-[1,3,4]triazin-4-yl)phenyl]-dibenzofuran-4-yl}-4,6-diphenyl-[1,3,5]triazine

33.4 g (70 mmol) of2-(6-bromodibenzofuran-4-yl)-4,6-diphenyl-[1,3,5]triazine, 24.7 g (70mmol) of 4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenylboronic acid and 78.9mL (158 mmol) of Na₂CO₃ (2 M solution) are suspended in 120 mL ofethanol and 100 mL of water. 1.3 g (1.1 mmol) of Pd(PPh₃)₄ are added tothis suspension, and the reaction mixture is heated under reflux for 16h. After cooling, dichloromethane is added to the mixture, and theorganic phase is removed, filtered through silica gel and recrystallizedfrom toluene. The yield is 42 g (59 mmol), corresponding to 85% oftheory.

Example 11 Preparation of2-(4-dibenzofuran-3-yl-phenyl)-4,6-diphenyl-[1,3,5]triazine

24 g (70 mmol) of 4-(4,6-diphenyl-1,3,5-triazin-2-ylphenyl)boronic acid,17.3 g (70 mmol) of 3-bromodibenzofuran and 78.9 mL (158 mmol) of Na₂CO₃(2 M solution) are suspended in 120 mL of ethanol and 100 mL of water.1.3 g (1.1 mmol) of Pd(PPh₃)₄ are added to this suspension, and thereaction mixture is heated under reflux for 16 h. After cooling,dichloromethane is added to the mixture, and the organic phase isremoved, filtered through silica gel and recrystallized from toluene.The yield is 28 g (58 mmol), corresponding to 86% of theory.

In an analogous manner, it is possible to prepare the followingcompound:

Reactant 1 Reactant 2 Product Yield

87%

Example 12 Preparation of2,4-diphenyl-6-[4-(6-trimethylsilanyl-dibenzofuran-3-yl)phenyl]-[1,3,5]triazine

To a solution, cooled to 20° C., of 57.4 g (121 mmol) of2-(4-dibenzofuran-3-yl-phenyl)-4,6-diphenyl-[1,3,5]triazine and 28 g(242 mmol) of TMEDA in 1000 mL of THE are added dropwise 127 mL (225.4mmol) of n-butyllithium (2.5 M in hexane). The reaction mixture isstirred at room temperature for 3 h, then cooled down to 0° C., and 26 g(242 mmol) of chlorotrimethylsilane are added dropwise within 30 min.The mixture is stirred at room temperature for 8 h. Subsequently, thesolvent is removed under reduced pressure and the residue is purified bychromatography using silica gel with chloroform as eluent. Yield: 41 g(74 mmol), 63% of theory.

In an analogous manner, it is possible to prepare the followingcompound:

Reactant 1 Product Yield

87%

Example 13 Preparation of3-[4-(4,6-diphenyl-[1,3,5]triazin-2-yl)phenyl]-dibenzofuran-6-boronicacid

Under protective gas, 21 g (86 mmol) of bromine tribromide are addeddropwise to a solution of 39 g of2,4-diphenyl-6-[4-(6-trimethylsilanyldi-benzofuran-3-yl)phenyl]-[1,3,5]triazinein 500 mL of dichloromethane and the mixture is stirred at roomtemperature for 10 h. Thereafter, a little water is added gradually tothe mixture and the precipitated residue is filtered off and washed withheptane. The yield is 32 g (62 mmol), corresponding to 87% of theory.

In an analogous manner, it is possible to prepare the followingcompound:

Reactant 1 Product Yield

90%

Example 14 Preparation of3-{7-[4-(4,6-diphenyl-[1,3,5]triazin-2-yl)phenyl]dibenzofuran-4-yl}-9-phenyl-9H-carbazole

36 g (70 mmol) of3-[4-(4,6-diphenyl-[1,3,5]triazin-2-yl)phenyl]-dibenzofuran-6 boronicacid, 22.5 g (70 mmol) of 3-bromodibenzo-furan and 78.9 mL (158 mmol) ofNa₂CO₃ (2 M solution) are suspended in 120 mL of ethanol and 100 mL ofwater. 1.3 g (1.1 mmol) of Pd(PPh₃)₄ are added to this suspension, andthe reaction mixture is heated under reflux for 16 h. After cooling,dichloromethane is added to the mixture, and the organic phase isremoved, filtered through silica gel and recrystallized from toluene.The residue is recrystallized from toluene and finally sublimed underhigh vacuum (p=5×10⁻⁵ mbar). The yield is 39 g (54 mmol), correspondingto 80% of theory.

In an analogous manner, it is possible to prepare the followingcompound:

Reactant 1 Reactant 2 Product Yield

87%

Example 15 Production and Characterization of the OLEDs

In examples C1 to 122 which follow (see tables 1 and 2), the data ofvarious OLEDs are presented. Cleaned glass plaques (cleaning inlaboratory glass washer, Merck Extran detergent) coated with structuredITO (indium tin oxide) of thickness 50 nm, for improved processing, arecoated with 20 nm of PEDOT:PSS (poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate), purchased as CLEVIOS™ P VP Al 4083 from HeraeusPrecious Metals GmbH Deutschland, spun on from aqueous solution). Thesecoated glass plaques form the substrates to which the OLEDs are applied.

The OLEDs basically have the following layer structure: substrate/holetransport layer (HTL)/interlayer (IL)/electron blocker layer(EBL)/emission layer (EML)/optional hole blocker layer (HBL)/electrontransport layer (ETL)/optional electron injection layer (EIL) andfinally a cathode. The cathode is formed by an aluminum layer ofthickness 100 nm. The exact structure of the OLEDs can be found intable 1. The materials required for production of the OLEDs are shown intable 3.

All materials are applied by thermal vapor deposition in a vacuumchamber. In this case, the emission layer always consists of at leastone matrix material (host material) and an emitting dopant (emitter)which is added to the matrix material(s) in a particular proportion byvolume by co-evaporation. Details given in such a form as INV-1:IC3:TEG1(60%:35%:5%) mean here that the material INV-1 is present in the layerin a proportion by volume of 60%, IC3 in a proportion of 35% and TEG1 ina proportion of 5%. Analogously, the electron transport layer may alsoconsist of a mixture of two materials.

The OLEDs are characterized in a standard manner. For this purpose, theelectroluminescence spectra, the current efficiency (measured in cd/A),the power efficiency (measured in lm/W) and the external quantumefficiency (EQE, measured in percent) are determined as a function ofluminance, calculated from current-voltage-luminance characteristics(IUL characteristics) assuming Lambertian radiation characteristics. Theelectroluminescence spectra are determined at a luminance of 1000 cd/m²,and the CIE 1931 x and y color coordinates are calculated therefrom. Theparameter U1000 in table 2 refers to the voltage which is required for aluminance of 1000 cd/m². CE1000 and PE1000 respectively refer to thecurrent and power efficiencies which are achieved at 1000 cd/m².Finally, EQE1000 refers to the external quantum efficiency at anoperating luminance of 1000 cd/m².

The data for the various OLEDs are collated in table 2. Examples C1-C8are comparative examples and show OLEDs containing materials accordingto the prior art. Examples I1-I22 show data for OLEDs comprisingmaterials of the invention.

Some of the examples are elucidated in detail hereinafter, in order toillustrate the advantages of the compounds of the invention. However, itshould be pointed out that this is merely a selection of the data shownin table 2. As can be inferred from the table, even when the compoundsof the invention that have not been specifically detailed are used,distinct improvement over the prior art are achieved, in some cases inall parameters, but in some cases only an improvement in efficiency orvoltage is observed. However, improvement in one of the parametersmentioned is already a significant advance because various applicationsrequire optimization with regard to different parameters.

Use of Compounds of the Invention as Electron Transport Materials

Compared to an OLED in which the material VG-6 according to the priorart is used in the ETL, a distinct improvement in voltage and efficiencyis observed when the materials INV-5, INV-7, INV-15, INV-21 and INV-20of the invention are used. Especially when the substance INV-5 is used,a voltage improved by 1.5 V compared to VG-6 is obtained, for instance a35% better external quantum efficiency and more than double the powerefficiency (examples C6, I5).

Use of Compounds of the Invention as Matrix Materials in PhosphorescentOLEDs

By inserting a phenyl ring between pyrimidine and dibenzofuran, it ispossible to improve the EQE by 15% and the voltage by 0.1 V (examplesC1, I1). This is true in an analogous manner of compounds comprisingtriazine (examples C2, I2, I3).

In addition, it is advantageous when a triazine or carbazole group isbonded face-to-face with respect to the dibenzofuran (examples C4, I2,I3). This is true in an analogous manner when the connecting groupbetween carbazole and triazine is not a dibenzofuran but a carbazole(examples C5, I4).

TABLE 1 Structure of the OLEDs HTL IL EBL EML HBL ETL EIL Ex. thicknessthickness thickness thickness thickness thickness thickness C1 SpA1HATCN SpMA1 VG-1:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10nm (50%:50%) 30 nm C2 SpA1 HATCN SpMA1 VG-2:TEG1 ST2 ST2:LiQ — 70 nm 5nm 90 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm C3 SpA1 HATCN SpMA1IC1:TEG1 — VG-7 LiQ 70 nm 5 nm 90 nm (90%:10%) 30 nm 40 nm 3 nm C4 SpA1HATCN SpMA1 VG-4:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10nm (50%:50%) 30 nm C5 SpA1 HATCN SpMA1 VG-5:TER1 — ST2:LiQ — 90 nm 5 nm130 nm (92%:8%) 40 nm (50%:50%) 40 nm C6 SpA1 HATCN SpMA1 IC1:TEG1 —VG-6 LiQ 70 nm 5 nm 90 nm (90%:10%) 30 nm 40 nm 3 nm I1 SpA1 HATCN SpMA1INV-1:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm(50%:50%) 30 nm I2 SpA1 HATCN SpMA1 INV-2:TEG1 ST2 ST2:LiQ — 70 nm 5 nm90 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm I3 SpA1 HATCN SpMA1INV-3:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm(50%:50%) 30 nm I4 SpA1 HATCN SpMA1 INV-4:TER1 — ST2:LiQ — 90 nm 5 nm130 nm (92%:8%) 40 nm (50%:50%) 40 nm I5 SpA1 HATCN SpMA1 IC1:TEG1 —INV-5 LiQ 70 nm 5 nm 90 nm (90%:10%) 30 nm 40 nm 3 nm I6 SpA1 HATCNSpMA1 INV-10:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm(50%:50%) 30 nm I7 SpA1 HATCN SpMA1 INV-6:TEG1 ST2 ST2:LiQ — 70 nm 5 nm90 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm I8 SpA1 HATCN SpMA1INV-7:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm(50%:50%) 30 nm I9 SpA1 HATCN SpMA1 IC1:TEG1 — INV-7 LiQ 70 nm 5 nm 90nm (90%:10%) 30 nm 30 nm 3 nm I10 SpA1 HATCN SpMA1 INV-8:TER1 — ST2:LiQ— 90 nm 5 nm 130 nm (92%:8%) 40 nm (50%:50%) 40 nm I11 SpA1 HATCN SpMA1INV-9:IC3:TEG1 IC1 ST2:LiQ — 70 nm 5 nm 90 nm (60%:35%:5%) 30 nm 10 nm(50%:50%) 30 nm I12 SpA1 HATCN SpMA1 INV-11:IC2:TEG1 IC1 ST2:LiQ — 70 nm5 nm 90 nm (45%:45%:10%) 30 nm 10 nm (50%:50%) 30 nm I13 SpA1 HATCNSpMA1 INV-12:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm(50%:50%) 30 nm I14 SpA1 HATCN SpMA1 INV-13:TEG1 ST2 ST2:LiQ — 70 nm 5nm 90 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm I15 SpA1 HATCN SpMA1INV-14:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm(50%:50%) 30 nm I16 SpA1 HATCN SpMA1 IC1:TEG1 — INV-15 LiQ 70 nm 5 nm 90nm (90%:10%) 30 nm 40 nm 3 nm I17 SpA1 HATCN SpMA1 INV-16:TEG1 ST2ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm I18SpA1 HATCN SpMA1 INV-17:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30nm 10 nm (50%:50%) 30 nm I19 SpA1 HATCN SpMA1 IC1:TEG1 INV-18 ST1:LiQ —70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm I20 SpA1 HATCNSpMA1 IC2:TEG1 INV-19 ST2:LiQ — 70 nm 5 nm 90 nm (90%:10%) 30 nm 10 nm(50%:50%) 30 nm I21 SpA1 HATCN SpMA1 IC1:TEG1 — INV-20 LiQ 70 nm 5 nm 90nm (90%:10%) 30 nm 40 nm 3 nm I22 SpA1 HATCN SpMA1 IC2:TEG1 — INV-21 LiQ70 nm 5 nm 90 nm (90%:10%) 30 nm 40 nm 3 nm

TABLE 2 Data of the OLEDs U1000 CE1000 PE1000 EQE CIE x/y at Ex. (V)(cd/A) (lm/W) 1000 1000 cd/m² C1 3.7 50 43 13.7% 0.33/0.62 C2 3.6 53 4514.4% 0.34/0.62 C3 3.6 56 49 15.5% 0.34/0.62 C4 3.4 52 49 14.1%0.33/0.62 C5 4.8 9.4 6.1 10.1% 0.67/0.33 C6 4.4 45 31 12.4% 0.34/0.62 I13.6 58 51 15.8% 0.33/0.62 I2 3.4 61 57 16.7% 0.33/0.62 I3 3.5 57 5115.6% 0.34/0.62 I4 4.6 10.5 7.1 11.3% 0.67/0.33 I5 2.9 62 68 16.9%0.34/0.63 I6 3.7 63 54 17.6% 0.33/0.63 I7 3.1 59 59 16.4% 0.34/0.62 I84.3 50 36 14.0% 0.39/0.59 I9 4.0 56 45 15.2% 0.33/0.62 I10 4.2 12.3 9.112.4% 0.67/0.33 I11 3.2 61 60 17.1% 0.34/0.62 I12 3.6 47 41 13.1%0.32/0.63 I13 3.2 51 50 14.4% 0.33/0.62 I14 3.6 59 52 16.6% 0.34/0.62I15 3.6 56 49 15.8% 0.33/0.62 I16 2.8 58 65 16.2% 0.32/0.63 I17 3.4 5651 15.5% 0.34/0.62 I18 3.7 53 46 15.0% 0.33/0.63 I19 3.6 58 51 16.1%0.32/0.63 I20 3.4 49 46 13.7% 0.35/0.61 I21 3.8 55 45 15.5% 0.35/0.62I22 3.0 49 51 14.5% 0.35/0.61

TABLE 3 Materials used

HATCN

SpA1

LiQ

TEG1

SpMA1

IC1

ST1

ST2

IC2

IC3

TER1

VG-1

VG-2

VG-3

VG-4

VG-5

VG-6

VG-7

INV-1

INV-2

INV-3

INV-4

INV-5

INV-6

INV-7

INV-8

INV-9

INV-10

INV-11

INV-12

INV-13

INV-14

INV-15

INV-16

INV-17

INV-18

INV-19

INV-20

INV-20

1.-21. (canceled)
 22. A compound of the general formula (1)

where the symbols and indices used are as follows: A and A′ are the sameor different and are an aromatic or heteroaromatic ring which has 5 or 6ring atoms and is optionally substituted by one or more R¹ radicalswhich is optionally independent of one another; G¹ is an organicelectron-transporting group (ETG) of the formula E-9 or E-10

Q′ is the same or different at each instance and is CR¹ or N, and wherethe dotted bond indicates the binding positions to the Ar¹ group orcarbon atom of the A group; G² is an electron-rich organic groupselected from the a group of the formula (L-18)-(L-30) and L(34)-L(36):

where dotted bonds indicate the binding positions to the Ar² group orcarbon atom of the A′ group, which may be substituted by one or moreindependent R² radicals; Ar¹ is a bivalent aromatic ring or ring systemhaving 6 to 60 ring atoms, where the ring or ring system is bridgedneither with the ring system comprising the A and A′ rings nor with theETG; Ar² is, when G² is an electron-transporting group, a bivalentaromatic ring or ring system having 6 to 60 ring atoms, where the ringor ring system is bridged neither with the ring system comprising the Aand A′ rings nor with the ETG, or, when G² is a hole-transporting group,an aromatic ring or ring system having 5 to 60 ring atoms, where thering or ring system is bridged neither with the ring system comprisingthe A and A′ rings nor with the LTG; V is O; W is a single bond, C═O,C(R¹)₂, NR¹, where, in the case of a single bond, the carbon atoms ofthe A and A′ rings are joined directly to one another by a single bond,C(R¹)₂, NR¹, O and S; m is either 0 or 1; n is either 0 or 1, where m=n;p is either 0 or 1; q is either 0 or 1, where p+q is either 1 or 2; R¹is the same or different at each instance and is H, D, F, Cl, Br, I, CN,NO₂, Si(R²)₃, B(OR²)₂, C(═O)R², P(═O)(R²)₂, S(═O)R², S(═O)₂R², OSO₂R², astraight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 carbonatoms or a straight-chain alkenyl or alkynyl group having 2 to 40 carbonatoms or a branched or cyclic alkyl, alkenyl, alkynyl, alkoxy,alkylalkoxy or thioalkoxy group having 3 to 40 carbon atoms, which isoptionally substituted by one or more R² radicals; where one or morenonadjacent CH₂ groups is optionally replaced by R²C═CR², C≡C, Si(R²)₂,Ge(R²)₂, Sn(R²)₂, C═O, C═S, C═Se, C═NR², P(═O)(R²), SO, SO₂, NR², O, Sor CONR² and where one or more hydrogen atoms is optionally replaced byD, F, Cl, Br, I, CN or NO₂, or an aromatic or heteroaromatic ring systemwhich has 5 to 60 aromatic ring atoms which is optionally substituted byone or more R² radicals; or an aryloxy, arylalkoxy or heteroaryloxygroup which has 5 to 60 aromatic ring atoms which is optionallysubstituted by one or more R² radicals; or a diarylamino group,diheteroarylamino group or arylheteroarylamino group which has 10 to 40aromatic ring atoms which is optionally substituted by one or more R²radicals, or a combination of two or more of these groups or acrosslinkable Q group; R² is the same or different at each instance andis H, D, F, Cl, Br, I, CN, NO₂, Si(R³)₃, B(OR³)₂, C(═O)R³, P(═O)(R³)₂,S(═O)R³, S(═O)₂R³, OSO₂R³, a straight-chain alkyl, alkoxy or thioalkoxygroup having 1 to 40 carbon atoms or a straight-chain alkenyl or alkynylgroup having 2 to 40 carbon atoms or a branched or cyclic alkyl,alkenyl, alkynyl, alkoxy, alkylalkoxy or thioalkoxy group having 3 to 40carbon atoms, which is optionally substituted by one or more R³radicals, where one or more nonadjacent CH₂ groups is optionallyreplaced by R³C═CR³, C≡C, Si(R³)₂, Ge(R³)₂, Sn(R³)₂, C═O, C═S, C═Se,C═NR³, P(═O)(R³), SO, SO₂, NR³, O, S or CONR³ and where one or morehydrogen atoms is optionally replaced by D, F, Cl, Br, I, CN or NO₂; oran aromatic ring system which has 6 to 60 aromatic ring atoms which isoptionally substituted by one or more R³ radicals; or an aryloxy,arylalkoxy or heteroaryloxy group which has 5 to 60 aromatic ring atomswhich is optionally substituted by one or more R³ radicals; or adiarylamino group, diheteroarylamino group or arylheteroarylamino groupwhich has 10 to 40 aromatic ring atoms which is optionally substitutedby one or more R³ radicals; or a combination of two or more of thesegroups; at the same time, two or more adjacent R² radicals together mayform a mono- or polycyclic, aliphatic or aromatic ring system; R³ is thesame or different at each instance and is H, D, F or an aliphatic, oraromatic radical having 1 to 20 carbon atoms, in which one or morehydrogen atoms may also be replaced by F; at the same time, two or moreR³ substituents together may also form a mono- or polycyclic aliphaticor aromatic ring system; with the proviso that not more than one R¹substituent in the A ring and not more than one R¹ substituent in the A′ring contains an aromatic or heteroaromatic group having 5 to 30 ringatoms.
 23. The compound as claimed in claim 22, wherein the compound isof the general formula (2)

where the symbols additionally used are as follows: X is the same ordifferent at each instance and is N or CR¹; Q is the same or differentat each instance and is X═X, S, O or NR¹.
 24. The compound as claimed inclaim 22, wherein the compound is of one of the following generalformulae (3) or (4):


25. The compound as claimed in claim 24, wherein the compound is of thegeneral formula (4).
 26. The compound as claimed in claim 24, whereinthe compound is of the general formula (4) where X is CR¹ and m is
 1.


27. The compound as claimed in claim 24, wherein the compound is of thegeneral formula (4) where X is CR¹, m is 1, p is 0 and q is
 1. 28. Thecompound as claimed in claim 22, wherein the compound is of the generalformula (13)

where V is O and where the aromatic rings each have not more than one R¹substituent, s is 0 or 1 and t is 0 or 1, where s+t is 0, 1 or
 2. 29.The compound as claimed in claim 22, wherein the compound is of thegeneral formula (15)

wherein s is 0 or 1 and t is 0 or 1, where s+t is 0, 1 or
 2. 30. Thecompound as claimed in claim 22, wherein the compound is of the generalformula (16)

wherein s is 0 or 1 and t is 0 or 1, where s+t is 0, 1 or
 2. 31. Thecompound as claimed in claim 22, wherein the compound is of the generalformula (16a).


32. A composition comprising at least one additional compound as claimedin claim 22 and at least one further compound selected from the groupconsisting of fluorescent emitters, phosphorescent emitters, hostmaterials, matrix materials, electron transport materials, electroninjection materials, hole conductor materials, hole injection materials,electron blocker materials and hole blocker materials.
 33. Thecomposition as claimed in claim 32, wherein the additional compound is ahost or matrix material.
 34. The composition as claimed in claim 32,wherein the additional compound has a band gap of 2.5 eV or more.
 35. Aformulation comprising at least one compound as claimed in claim 22 andat least one solvent.
 36. An electronic device comprising at least onecompound as claimed in claim
 22. 37. An electronic device comprising atleast one compound as claimed in claim 22 in an emission layer (EML),electron transport layer (ETL) or in a hole blocker layer (HBL).
 38. Theelectronic device as claimed in claim 36, wherein the device is anorganic integrated circuit (OIC), an organic field-effect transistor(OFET), an organic thin-film transistor (OTFT), an organicelectroluminescent device (OLED), an organic light-emittingelectrochemical cell (OLEC, LEEC, LEC), an organic solar cell (OSC), anorganic optical detector, or an organic photoreceptor.
 39. Theelectronic device as claimed in claim 37, wherein the device is anorganic electroluminescent device which is selected from the groupconsisting of organic light-emitting transistors (OLETs), organic fieldquench devices (OFQDs), organic light-emitting electrochemical cells(OLECs, LECs, LEECs), organic laser diodes (O-lasers) and organiclight-emitting diodes (OLEDs).
 40. A process for producing an electronicdevice as claimed in claim 36, which comprises applying at least oneorganic layer by gas phase deposition or from solution.
 41. Theelectronic device as claimed in claim 40 for use in medicine forphototherapy.
 42. The compound as claimed in claim 22, wherein thecompound is of the general formulae (3):


43. The compound as claimed in claim 22, wherein the compound is of oneof the following general formulae (5) to (11):


44. The compound as claimed in claim 22, wherein each R¹ isindependently selected from the group consisting of H and an aromatic orheteroaromatic ring system having 5 to 60 aromatic ring atoms, each ofwhich is optionally substituted by one or more R² radicals.
 45. Thecompound as claimed in claim 22, wherein G¹ is an organicelectron-transporting group (ETG) of the formula E-10.
 46. The compoundas claimed in claim 22, wherein G¹ is selected from the group consistingof quinolines, isoquinolines, and quinoxalines, which are optionallysubstituted by one or more R¹.
 47. The compound as claimed in claim 22,wherein G¹ is a quinoxaline, which is optionally substituted by one ormore R¹.
 48. The compound as claimed in claim 43, wherein the compoundis of general formula (8).